1. Field of the Invention
The present invention relates to an image processing system, an image processing apparatus, and a control method and program therefor.
2. Description of the Related Art
Hitherto, in an image processing apparatus, such as a multi-function peripheral apparatus for transmitting image data created by scanning a document image through a network and storing it in another apparatus, the received data is stored while being attached with a unique identifier.
However, if a transmitter finds a mistake in a document after transmitting the document and if the transmitter retransmits the document, both the document transmitted first and the retransmitted corrected document are stored in an apparatus on a receiver side. Therefore, the receiver cannot easily determine which of these similar documents is the correct document. Further, if an already transmitted file is retransmitted by compressing it or by changing its file format because a size of the transmitted file is too large, the unnecessary file transmitted first remains in the apparatus.
In order to solve this problem, Japanese Patent Laid-Open No. 2002-135499 suggests the following technique. That is, in a process of transmitting image data to a destination apparatus, it is determined whether already transmitted image data is stored in the same destination apparatus. If the destination apparatus has the transmitted image data, a process required by the destination apparatus is executed.
In the system described in the above-mentioned patent document, however, image data is identified based on its attribute information. Therefore, image data having different attribute information is regarded as different image data, which cannot be replaced.